In his French patent applications with national registration numbers 9501518 and 9502212, the author has described a cyclic internal combustion engine method, the engine having a constant-volume independent combustion chamber, in which the compression chamber, the combustion chamber and the expansion chamber consist of three separate and entirely independent parts, thus allowing each of the three elements to be adapted to suit the function assigned to it without interfering with one another, as well as a system for controlling expansion (9502212) that makes it possible to make the maximum expansion pressure coincide with a crank angle that gives a high tangential force, further improving the overall efficiency of this type of engine.
However, when running in urban areas, especially with cars, the engine still consumes fuel which means that there are still polluting emissions even though these are very substantially reduced.